Modeling the Impact of Increasing PHEV Loads on the Distribution Infrastructure

Abstract

Numerous recent reports have assessed the adequacy of current generating capacity to meet the growing electricity demand from Plug-in Hybrid Electric Vehicles (PHEVs) and the potential for using these vehicles to provide grid support (Vehicle to Grid, V2G) services. However, little has been written on how these new loads will affect the medium and low-voltage distribution infrastructure. This paper briefly reviews the results of the existing PHEV studies and describes a new model: the PHEV distribution circuit impact model (PDCIM). PDCIM allows one to estimate the impact of an increasing number of PHEVs (or pure electric vehicles) on transformers and underground cables within a medium voltage distribution system. We describe the details of this model and results from its application to a distribution circuit in Vermont.

A case study of coordinated electric vehicle charging for peak shaving on a low voltage grid

“…Therefore, the impact of coordination on the technical lifetime of the distribution system assets, e.g. transformers and cables [12], [13], must be analyzed. The exploitation costs of the distribution system may increase if the technical lifetime of the assets is reduced below the economic and strategic lifetime.…”

“…Aging is considered an exponential function of the hot spot temperature, which in turn depends on the currents flowing through the transformer. Therefore, an increase in peak loading, due to uncoordinated EV charging, has a significant influence on aging of transformers that are already operating close to their limits [13], [15].…”

“…Furthermore, load shifting, that is the re shaving objective for EV charging, will fla profile of the transformer [13]. This reduces expansion and contraction of the transform mechanical stresses on the components.…”

“…Distribution grid topology used in the simulation Therefore, peak cable aging. 8 is a conservative because dynamic mperature are not dynamic loading nd conventional ke overvoltage and res than aging of age are more esult of the peak atten out the load the daily thermal mer, thus reducing is could decrease ussed in [13]. duce net injection m the LV into the o charge the EVs.…”

Smart Charging Systems for Plug-in Electric Vehicles

“…Previously referenced studies on the effects of PHEV loading on distribution transformers [3,4,5,6] lead us to consider mitigation schemes that leverage monitoring, communications and control technologies that are utilized in smart grid applications. These schemes may take the form of edge control networks or centralized control networks.…”